Baskin D S, Simpson R K
Neurosurgery. 1987 Jun;20(6):871-7. doi: 10.1227/00006123-198706000-00009.
Somatosensory evoked potentials (SSEPs) and corticomotor evoked potentials (CMEPs) were utilized to study acute blunt spinal cord trauma. Rats, anesthetized with ketamine hydrochloride, were subjected to a parasagittal craniotomy and a midthoracic laminectomy. SSEPs were cortically recorded and CMEPs were transcortically produced using epidural ball and disc electrodes. SSEPs were elicited and CMEPs were recorded via hindlimb percutaneous needle electrodes. After control records were made, animals were subjected to a 25-, 50-, or 75-g/cm impact to the dorsal cord surface via a modified weight drop procedure. Evaluation of neurological injury was made by SSEP and CMEP analysis as well as by physical testing with noxious stimulation applied to the hindlimb. Neurohistopathological verification of each spinal cord lesion was performed. No significant change in SSEP configuration was identified in animals subjected to a 25-g/cm cord impact; however, a small decrement in CMEP amplitude was consistently observed. Although vocalization to noxious stimulation was present, flexion activity was less than normal. Animals subjected to a 50-g/cm cord impact also showed no change in SSEP wave forms. All components of the CMEP were greatly attenuated with this injury. Either very weak movement or no movement to noxious stimulation was present without vocalization. After a 75-g/cm cord impact, both SSEPs and CMEPs were abolished. There was no movement or vocalization in response to noxious stimulation. Serial sections of the spinal cords revealed incremental destruction with increasing severity of injury. These results support the hypothesis that CMEPs are a more sensitive indicator of residual spinal cord function after injury than are SSEPs.
体感诱发电位（SSEPs）和皮质运动诱发电位（CMEPs）被用于研究急性钝性脊髓损伤。用盐酸氯胺酮麻醉的大鼠接受矢状旁开颅术和胸段中段椎板切除术。使用硬膜外球电极和盘状电极皮层记录SSEPs，并经皮层引出CMEPs。通过后肢经皮针电极引出SSEPs并记录CMEPs。在进行对照记录后，通过改良的重物下落程序对动物的脊髓背侧表面施加25、50或75 g/cm的撞击。通过SSEP和CMEP分析以及对后肢施加有害刺激的物理测试来评估神经损伤。对每个脊髓损伤进行神经组织病理学验证。在接受25 g/cm脊髓撞击的动物中，未发现SSEP构型有明显变化；然而，始终观察到CMEP波幅有小幅下降。尽管对有害刺激有发声反应，但屈曲活动低于正常水平。接受50 g/cm脊髓撞击的动物SSEP波形也未显示变化。这种损伤使CMEP的所有成分都大大减弱。对有害刺激要么运动非常微弱，要么没有运动且无发声反应。在接受75 g/cm脊髓撞击后，SSEPs和CMEPs均消失。对有害刺激无运动或发声反应。脊髓连续切片显示随着损伤严重程度增加，破坏程度逐渐加重。这些结果支持这样的假设，即与SSEPs相比，CMEPs是损伤后脊髓残余功能更敏感的指标。
